1. Field of the Invention
This invention pertains generally to high definition wide aspect ratio (e.g. 16:9, also referred to as 51/3:3) television systems. More particularly, it pertains to methods and apparatus for providing improved horizontal resolution of luminance and chrominance in high definition television systems that decompose and repackage the high definition wide aspect ratio image signal into two signals for distribution over two channels. The first signal is a center image signal transmitted via a first channel in standard (e.g., NTSC) format and when received by a standard television receiver, produces the center image having a 4:3 aspect ratio. The second signal is an enhancement signal transmitted via a second channel. The enhancement signal contains, among other information, side panel image signals which, together with the center image signal, enable a two channel receiver to reproduce the original wide aspect ratio image. The enhancement signal also carries additional information for the center image that cannot be accommodated by a standard TSC signal.
2. Description of Related Art
Various features of such a system are described and illustrated in U.S. Pat. No. 4,694,338 "A High Definition Television System" and U.S. patent application, Ser. No. 06/931,756, filed Nov. 17, 1986, "1-Channel Video Signal Delivery System", both in the name of Mikhail Tsinberg, common assignee; U.S. patent application, Ser. No. 057,849, filed June 2, 1987 "Decomposition and Recombination of a Wide Aspect Ratio Image"; U.S. patent application, Ser. No. 057,847, filed June 2, 1987. "Methods and Apparatus for Transmitting Augmentation Panel Components on One Channel of a Two Channel Wide Aspect Ratio Television Signal Transmission System"; U.S. patent application, Ser. No. 057,848, filed June 2, 1987 "Improved Method and Apparatus for Recombining a Main Panel Component with an Augmentation Panel Component to Create a Wide Aspect Ratio Television Display"; and U.S. patent application, Ser. No. 07/057,880, filed June 2, 1987 "Method and Apparatus for Demodulating Color Television Chrominance Signals", all in the names of Mikhail Tsinberg, Carlo Basile, and Alan P. Cavallerano, common assignee.
While some enhancement of the center image signal that is compatible with standard receivers is possible, utilization of the available bandwidth is limited by the standard broadcast format. Given this limitation on the utilization of the bandwidth of the first channel, it is desirable to achieve increased utilization of the available bandwidth in the second channel.